1. Technical Field
the invention relates to a printing control device, which controls the printing section in the printing apparatus, a printing apparatus, and a printing control method in the printing apparatus.
2. Related Art
For example, JP-A-2004-25551 discloses a printing apparatus which includes a plurality of recording heads (fluid ejecting sections) for ejecting ink. In the printing apparatus, a carriage, which is provided to be able to reciprocate, is equipped with: a plurality of printing heads; and a plurality of driving control sections that controls driving of the plurality of printing heads. Further, the main body of the printing apparatus is equipped with a plurality of data processing sections that transfers data to the respective driving control sections. The main control unit, which controls the reciprocation of the carriage, is connected to a plurality of circuit groups each of which is formed of one driving control section and one data processing section per a predetermined number of printing heads. In this configuration, processing is shared among circuits belonging to the single circuit group per the predetermined number of printing heads. Therefore, according to the printing apparatus, processing load per one data processing section is reduced.
Further, a large number of recording heads may be provided. In this case, two or more main control units are provided, and a printing control device, in which the main control units, the data processing section, and the driving control section are formed as a single circuit group, is constituted by a single substrate, and the printing apparatus is configured to include a plurality of the substrates. In such a configuration of the printing apparatus, the plurality of recording heads is shared and controlled by the plurality of printing control devices. Hence, as the number of recording heads increases, the number of printing control devices increases. In such a manner, while relatively reducing load per one printing control device, it is possible to secure a necessary printing process speed.
Further, the following configuration may be adopted: each printing control device, which is for controlling the plurality of recording heads, and the driving control device, which controls driving of the carriage and transport of the printing medium (the sheet), is separately formed; and each printing control device transmits the command, which is acquired from the print data, to the driving control device. In this case, it is necessary to synchronize the output timing of the commands, which are issued from the respective printing control devices to the driving control device, with each other. For example, one printing control device is set as a master (a master-side printing control device), and another printing control device is set as a slave (a slave-side printing control device). In addition, the master-side printing control device is configured to transmit commands to the driving control devices (a mechanical controller and the like) of a carriage system and a transport system when the command received from the slave-side printing control device is synchronized with its own command. With such a configuration, it is possible to appropriately control the timing for performing an ink ejecting process of each recording head controlled by another printing control device and the timing for performing the transport process of the printing medium controlled by the driving control device.
Further, not only the plurality of recording heads may be shared among the plurality of printing control devices, but also even a plurality of components such as a plurality of ink cartridges, which supplies ink to the recording heads, and a nozzle test device, which tests nozzle clogging of the recording heads, provided in the printing apparatus may be shared among and connected to the plurality of printing control devices, thereby sharing load among the respective printing control devices. Here, normally, the ink cartridge is provided with a storage element in which ink-related information on a remaining ink level, an ink color, and the like is stored, and each printing control device accesses the storage element of the associated ink cartridge, thereby sharing and managing the ink-related information on remaining ink levels of ink types.
However, in the plurality of printing control devices, in some cases, only a certain printing control device may individually generate a command (an internal command) from the inside thereof. Examples of the internal commands, which are generated inside the printing control device, include an ink running out error (an ink end error) of an ink cartridge associated with a printing control device, a nozzle clogging error of a nozzle test device, and errors in components such as an associated recording head, an ink cartridge, a nozzle test device, and the like.
As it is, for example, when an internal command is generated from the master-side printing control device, the internal command is not generated from another slave-side printing control device. For this reason, when the master-side printing control device outputs an internal command, although the master-side printing control device waits for the same internal command from the slave-side printing control device in order to perform synchronization, no command is received, and thus a timeout occurs in the synchronization processing. As a result, a problem arises in that it is difficult to output the internal command.